Pneumatic tool



\ May 25 1926.

c. sAULlA PNEUMATIC TOOL Filed May 22, 1924 INVENTOR QVHRLEISQSHUL /H HIS ATTORNEY Patented May 25, 1926.

UNITED STATES CHARLES SAULIA, F BRQOKLYN, NEW YORK.

PNEUMATIC TOOL.

Application led Hay 22,

This invention relates to pneumatic tools and articularly to those in which a plurality o pneumatic hammers are mounted in the same frame or part for use simultaneously.

3 Such devices are commonly employed for l cutting or cleaning walls such as for removing barnacles or encrustations from the `sides of ships, bridges, and chipping or cutting rock walls, etc. `In these devices a plurality of chisels are actuated independently of one another by separate pneumatic hammers mounted in a common frame or base, so that a single operator may manipulate all of the" tools at one time. An object 1I of the invention is to provide an improved multiple pneumatic tool in which the construction Will be generally simplified, made more eiicient, reliable and durable, which will be automatic in action and relatively inexpensive, and in which the vibration will be reduced to a minimum. Various other objects and advantages will be apparent from the followin description of an embodiment of the invention, and the novel features I l5 will be particularly pointed out hereinafter in claims.

In the accompanying drawing, Figure 1 is a sectional elevation of a multiple tool which is constructed in accordance with the invenlc tion, and

Fig. 2 is a sectional plan of the same, the section being taken substantially along the line 2 2 of Fig. 1. r

Referring to the drawing, the particular .85 detail which is illustrated comprises a base block or frame 1 with plates 2 and3 secured against opposite faces thereof by any suitable means, such as by bolts 4, which pass through the plate 2 and 3 and the body part 4 or frame. The block is provided with a plurality ofv apertures or bores 5 which pass between the faces covered by the cap plates 2 and 3 and may be of equal diameter. One of the cap plates, such as 2, is provided with apertures 6 which are aligned with the apertures or bores 5. Bushings 7, 8 and 9 are disposed in the apertures or bores 5 and each bushing has a reduced extension 10 which passes through the aperture 6 aligned with the bore in which it is placed, so that the extension will project through the cap plate 2 to some extent. One ofthe bushings, such as 7, is provided with two 1924. Serial No. 715,110.

bores 11 and 12 of different cros's sectional area, the smaller bore 12 extending through 55 the'reduced extension 10. A piston hammer 13 1s mounted for reciprocation inthe bore 11 and is provided with a reduced end extension 14 which reciprocates in the reduced bore 12. The length of the piston hammer 13 shorter than the bore 11, so that it may reciprocate to some extent'endwise therein with the extension 14 reciprocating in the bore 12. 't

The piston is provided ashort distance from each end with annular grooves 15 and 16 and with a transverse passage 17 communicating with one of the grooves, suc-h as 16. The piston is also provided with a passage 18 extending from one end face 70 such as the upper end face closed by the cap 3 to the transversepassage 17 so that the annular groove 16 will at all times be in communication with the chamber at the end of the bore 11 which is closed by the 75 cap plate 3. The piston hammer 13 is also provided with passages 19 which connect the other annular groove 15 with the opposite end of the hammer, which is at the shoulder between it and its reduced extension 14. It will thus be observed that each annular groove is connected by separate passages to the opposite end face of the piston.

The bushing 7 is also providedv adjacent, 85 one end with an exhaust port 20 and at a similar distance from the opposite end of the bore with an exhaust port 21. Intermediate these exhaust ports 20 and 21 the bushing is also provided with an inlet port 22 positioned so that as the piston hammer reciprocates in the bushing, the annular grooves will alternately communicate with one of the exhaust ports and the inlet port. The bushings 8 and 9 are provided with 95 similar parts .designated by similar characters, with the exponents a and lo, the parts being similar in all respects, except that they are arranged to have v different distances of travel or reciprocation. To obtain this the bores 11, 11, and 11b are made of different lengths and the annular grooves and ports are similarly proportioned and disposed so that the piston hammers will operate perfectly through similar but different distances of reciprocation.. The inlet v common supply conduit 23, which is su plied with a compressed actuating fluid through a supply pipe 24. A suitab e valve 25 may be provided with the conduit 23 for controlling the admission of the compressedl fluid to the inlet ports. The bearing block or 'frame 1 is rovided with exhaust conduits 26 and 27 w 'ch communicate respectively with the exhaust ports 20 and 21.

When a compressed Huid is admitted to the inlet port 22 of the bushing 7, and assuming the piston hammer to be at its lowermost position, such as shown in the bushing 8, the fluid will enter the annular groove 15 and pass through the passages 19 to the lower shouldered face of the piston, with the result that the pressure upon the shouldered face and the walls of the annular roove will be sufficient to force the piston iammer upwardly toward the cap plate 3. As the piston hammer travels upwardly the Huid in the upper end of the bore will escape through the exhaust port 20 and axhaust conduit 26. As soon as the piston hammer has traveled a short distance, the roove 15 will move out of communication with the inlet port,'and thereafter the movement will be continued by the ex ansi on of the already admitted compressed uid. When the upper end of the piston reaches and passes the exhaust port 20, the duid trapped therein will act as a cushion for stopping the upward travel of the piston. During the upf ward travel of the piston hammer, air w1ll be drawn into the lower end of the bore through the exhaust conduit 27 and exhaust port 21, which is opened by the upward travel of the piston. When the piston has nearly reached its upward limit of travel, as shown at the left in Fig. 1 in the bushing 9, the annular groove 16 will be in communication with the inlet port and the compressed luid will then ass through the transverse passage 17 an the longitudinal passage 18 to the upper end of the bore and force the piston hammer downwardly, the air which has entered the lower end of the bore escaping from the exhaust port 21. As the piston moves downwardly the groove 16 will move out of communication with the inlet port, with the result that the compressed iiuid will be cut off and the action continued by thel expansion of the compressed uid which has already been admitted. lVhen the lower or shouldered face of the piston passes the exhaust port 21, the fluid or air trapped in the lower end of the bore will act as a cushion to check the downward travel of the piston hammer, but since this would be suiiicient to destroy or retard the action of the piston hammer upon the tool, should the tool be in a position to be struck, a vent 28 is provided in the lower end of the bushing for communication with a vent passage 29 leading to the atmosphere.. This will allow the descent of the piston hammer through its full length, but will slightly cushion the downward blow, 1n case the tool is not in position to take the blow.

A small sleeve 30 is inserted in the lower end of the reduced extension 10 and mounts a tool .31 for reciprocation in a direction parallel with the reciprocation of the hammer, the inner end of the tool having a flange to prevent its removal from the sleeve 30. When the tool is pushed against a surface it will move into the bore 12 into the path of the piston hammer so as to be struck by the latter in its reciprocation. The bores are made of different lengths as indicated in Fig. 1 by the parallel datum lines 8^, 7^', and 9A, whereby the piston hammers are given different lengths of travel, so that they cannot continue synchronous reciprocation. If at any time they should all make synchronous strokesupon the hammer, they will operate differently the next stroke, for the reason that their lengths of travel are different and therefore they cannot continue v to operate synchronously. By this arrangement the vlbration of each piston hammer will be more or less neutralized by the vibrations or tendency to vibrate set up by the other pistons and an attendant or o erator can more readily control and manipu ate the combined multiple acting tool.

The bores or apertures 5, are preferably provided with annular grooves 32 and 33 which are in communication with the exhaust ports 20 and 21, so that if the bushings should rotate in the bores 5, the exhaust ports will always be effective.

Thecap plate 3 serves to confine the bushings 7, 8 and 9 within lthe bearing block or frame l and to close the u per ends of the bores. 2Ihe passages 26, 2 29 are so arranged that they may be drilled or otherwise cut in a simple and convenient manner.

It will be obvious that various changes in the details which have been herein described and illustrated for the purpose of explaining the'nature of the invention may be made by those lskilled in the art within the principle and the scope of the invention as expressed in the appended claims.

I claim: A

1. A. pneumatic tool comprising a body having a plurality of separate piston chambers extending in the same direction and of different lengths, pneumatically actuated pistons in said chambers reciprocating from end to end thereof, and separate tools carried by said pistons so as to be operated therefrom, the chambers of different lengths preventing continued synchronous recipro! cations of said pistons.

2. A pneumatic tool comprising a body having a plurality of parallel bores extendder the action of a compresse fluid deliving from face to face, plates covering both ered to said ports, said piston hammer 'hav- 'of said faces, sleeves havin piston chambers ing passa es c-operating with the said ports of different lengths inserte in said bores and to contro properly the reoiprocations autol confined therein .by said plates, said sleeves matically. p l 5` having inlet and outlet ports, and a piston In testimony whereof I have hereunto set hammer in each sleeve for reci rcation unmy hand. y

1 CHARLES SAULIA.- t 

